> Protected methods can be invoked on self or with an implicit receiver. No, protected method can be called on self or from other instances of the same class.

> Protected methods can be invoked on self or with an implicit receiver. No, protected method can be called on self or from other instances of the same class. Typically used for implementing `==` methods. > Private methods can only be invoked on an implicit receiver. That used to be true, but as others mentioned is no longer true as of Ruby 2.7.